Why major airports are struggling with terminal crowding and security bottlenecks this winter

The world’s biggest airports are seeing unusually crowded terminals and security bottlenecks as the winter 2025 travel season reaches its peak. Passengers at major hubs in Europe and North America are encountering longer lines at check in, security screening, and border control, with some terminals filled wall to wall during the busiest hours. The pressure comes as holiday travel demand has returned to record levels. In response, airport authorities and airlines are offering guidance to help travelers move through the congestion with less stress.

Why winter airport congestion is rising again

After years of travel restrictions, passenger numbers have rebounded to all-time highs in many countries. In the UK, regulators confirm that more people are flying now than ever before.

Airports are on track for the busiest Christmas in history, with over 22 million passengers expected to pass through UK airports this December – surpassing last year’s record.

A similar trend is playing out in North America, where the U.S. Transportation Security Administration (TSA) has recorded eight of its ten busiest days ever during 2025 alone. Airlines have added extra flights around the holidays to meet demand, and global seat capacity this winter slightly exceeds pre-pandemic levels.

All this means winter travel crowds are back – and often bunched into intense peaks. Unlike summer, winter schedules tend to concentrate flights around holiday weeks and weekends, compressing huge volumes of travelers into a few key days. For example, airlines reported nearly 10 million U.S. passengers over the Christmas-New Year period last year, with particular days like the Friday before Christmas setting new records.

When so many people fly on the same day, even small disruptions can create long queues. A brief snow flurry or a slower baggage check-in can ripple through a fully booked day’s schedule, because there’s little slack. Airport operations experts note that during these peak waves, a minor delay can quickly cascade – one late flight or an understaffed checkpoint might back up thousands of passengers in a domino effect.

Travelers are also carrying post-pandemic habits into this winter. Many are making long-postponed family trips or big vacations, meaning flights are packed and luggage loads are heavy. Airports say leisure passengers sometimes arrive less organized (with extra bags or gifts), which can slow down processes like security. In short, winter 2025 has brought a perfect storm of record passenger demand and seasonal challenges, making some terminals feel as crowded as a shopping mall on Christmas Eve.

The hubs feeling the most pressure

Not all airports are equally squeezed. A few major hubs have emerged as hotspots of congestion this winter due to their size, staffing situations or local circumstances:

London Heathrow (LHR)

Britain’s biggest airport is seeing near-record traffic, with around seven million passengers expected in December alone. Heathrow handled more than 83 million people over 2024 – surpassing its 2019 peak – and is forecasting even more in 2025.

The airport insists it is maintaining service standards (in 2024 it said 92% of passengers cleared security in under 5 minutes ), but terminals are undeniably busy. Early mornings at Heathrow are especially hectic as transatlantic red-eyes arrive and European short-haul flights depart. The airport has invested in upgrading security lanes and other infrastructure to cope with growth , yet this winter there are still reports of dense crowds at security and immigration during peak hours.

Heathrow is urging travelers not to panic but to allow plenty of time and “check for disruption, including on your route to the airport” in case of winter weather. So far, the hub has avoided any major meltdown, but it remains under heavy pressure from the sheer volume of holiday flyers.

Amsterdam Schiphol (AMS)

Schiphol was infamous for severe queues in summer 2022, and while conditions improved after hiring more staff, Amsterdam’s hub is still under strain. Passenger traffic has grown about 3% this year, with 6.2 million people passing through in October 2025.

That’s despite the Dutch government imposing flight caps to reduce noise, meaning almost the same number of flights carried more passengers than before. The airport has taken novel steps to manage flow – for example, it introduced a system for travelers to reserve a security screening time slot in advance to avoid waiting.

Even so, busy waves continue to test Schiphol’s capacity. It remains one of Europe’s busiest transfer hubs and saw long lines earlier this year when security staffing briefly fell short. Typical pinch points are the early morning departure rush (many Europe-bound flights leave before 9 a.m.) and mid-afternoons when intercontinental flights bank through.

Schiphol officials report that all security lanes are open and new CT scanners are speeding up bag checks, but they acknowledge the terminal can feel crowded and “log jammed” when demand peaks. Dutch unions have warned that if staffing doesn’t keep up, queues “as long as 2022” could return in the future – a cautionary note as passenger numbers climb.

Munich Airport (MUC)

Germany’s second-largest hub is known for its efficiency, yet winter brings particular challenges. Munich is a major gateway for ski tourism and holiday markets, which swells passenger counts on weekends. It’s also in a region prone to snow and freezing fog.

Already this November, a combination of freezing fog and staff sickness caused a messy day at Munich: ground crews struggled with a surge in de-icing, leading to 18% of staff calling in sick and nearly 860 flight delays across Germany, with Munich among the worst hit. Lufthansa had to cancel multiple flights and warned of knock-on delays. This shows Munich’s vulnerability when weather and staffing issues collide.

The airport is currently expanding Terminal 1 (with a new pier under construction for 2026) but during works the existing facilities must handle all traffic. Crowding can peak when snow disrupts the schedule, forcing waves of passengers to linger in gate areas. Munich’s management says contingency plans are in place for the Christmas rush, and they have ample de-icing rigs and winter ops teams on standby.

Still, passengers should expect occasional bottlenecks – for example, if multiple flights get rescheduled at once or if inbound delays cause hundreds of people to rebook connections. Munich’s status as a generally well-run airport means lines move in an orderly way, but at times this winter it has been “standing room only” in departure halls as travellers queue for security and boarding.

Madrid Barajas (MAD)

Spain’s main international hub has been especially hard-hit by bottlenecks in recent weeks. Madrid handled about 140,000 passengers and 1,000 flights on a typical day this month , making it the fifth-busiest airport in Europe. That heavy throughput was tested on 2 December, when a small group of disgruntled security screeners launched a surprise work-to-rule slowdown during the morning rush.

Only 21 staff deliberately followed every procedure to the letter and refused to rotate between lanes – and within 90 minutes, security wait times in Terminal 4 blew out to almost 50 minutes. (Normally, Aena – the airport operator – aims to keep priority security waits under 15 minutes.) The result was dozens of passengers missing flights and a cascading delay for later departures.

Although supervisors eventually called in extra off-duty staff to clear the queues by midday , the incident was a stark reminder of how vulnerable the airport is to even a brief slowdown. Barajas is also contending with nationwide labor unrest: a rolling ground-handling strike is planned to hit many Spanish airports (including Madrid) on multiple days each week through the end of December.

These intermittent strikes by baggage handlers may not stop flights, but they are expected to cause longer lines at check-in and slower baggage delivery. Madrid’s management has activated contingency plans – including using civil guard personnel to support airport security if needed – to get through the holiday crunch.

Passengers using Madrid should build in extra time and stay alert for official advisories, as the combination of peak crowds and sporadic labor actions is creating unpredictable conditions.

These four hubs illustrate the variety of pressures airports face: sheer passenger volume (Heathrow), prior capacity issues (Schiphol), weather and seasonal surges (Munich), and labor/staffing hiccups (Madrid). Other major airports in Europe and North America are also busy – from Paris and Frankfurt to New York JFK and LAX – but the above hubs have issued some of the most visible warnings and seen the most notable bottlenecks so far this winter.

How security bottlenecks actually form

Most travelers experience congestion first and foremost at the security checkpoint. This is often the tightest choke point in an airport, and it can become a frustration flashpoint in winter. But why do security lines sometimes snake for hundreds of feet? Several dynamics are at play:

Staffing and lane availability: Security screening is labor-intensive. Airports roster a certain number of officers and open a fixed number of X-ray lanes based on anticipated passenger loads. If that staffing falls short – for example, due to unexpected absences or a sudden surge of travelers – lines grow.

Closing just one lane (for maintenance or because no staff is available to operate it) can significantly slow the flow. Airports set service targets (like TSA aiming for under 30 minutes wait in standard lanes , or Heathrow striving for under 5 minutes for most passengers ), but at peak times they often deploy all available staff and still see queues.

Unpredictable surges make it hard to perfectly match lane capacity to demand: if several large tour groups show up early, or if a bank of delayed flights causes hundreds of passengers to re-enter security at once, the checkpoint can get overwhelmed even if it was fine minutes earlier.

Security agencies acknowledge that during holiday peaks, screening lines will be longer despite best efforts. As one U.S. expert noted, with record traveler numbers “even more time factored into your airport experience can’t hurt”.

Thorough screening vs. speed: Winter can actually slow the screening process for each passenger. One reason is clothing – in cold months people wear bulky coats, boots and layers that all must come off and go through the X-ray. “All those extra layers people wear in winter…take some time to remove and put back on at security checkpoints, slowing things down” explained a TSA security director.

Heavy winter boots often set off metal detectors, meaning more pat-downs. Additionally, winter travelers might carry unusual items: think skis and snow gear, wrapped Christmas presents, or food gifts. These often trigger extra inspection. The UK Civil Aviation Authority has warned that seemingly harmless holiday items – like Christmas crackers, lithium batteries and wrapped gifts – can cause queues at security if they aren’t packed correctly.

Security officers may have to manually check bags full of electronics or dense clothing, which takes time. In a recent case at Madrid, a “work-to-rule” protest involved screeners meticulously inspecting every bag and following all protocols strictly – the result was a near doubling of wait times within an hour.

This shows how the balance of thoroughness vs. speed affects throughput. Even without a protest, winter tends to require a bit more thoroughness: officers must discern a cluttered carry-on stuffed with sweaters and gadgets, versus a light summer bag.

Equipment and process factors: Modern airports are upgrading to CAT or CT scanners that allow laptops and liquids to stay in bags, which will help speed things up. But these machines are costly and still rolling out. In the meantime, many checkpoints use older X-rays where each bin must be manually reviewed.

If a machine needs recalibration or a new image review, the line pauses momentarily – and a long queue can build from just a few such pauses. If one passenger forgets the rules (for example, accidentally leaving a bottle of water or an iPad in their bag), their bag gets pulled aside, and an officer has to resolve it while the X-ray conveyor waits.

Multiply that by dozens of passengers with extra gadgets and you see how “little delays add up” in the security line. The TSA notes that standard lanes handle about 150-200 people per hour under normal conditions; drop that to 100 per hour due to winter coats and miscues, and soon hundreds of people are waiting.

This winter’s high traveler counts mean the margin is slim. Airports urge flyers to help by arriving early, organizing their carry-ons (know what must come out or be declared), and being ready for screening – all to keep those lanes moving. Many have published reminders on what not to pack or how to speed up your time in line (for instance, Heathrow’s holiday tips include packing liquids/gels in the top of your bag for easy access and not wrapping presents until after your flight, so security doesn’t have to unwrap them).

Ultimately, security lines will still grow during rush hours, but understanding why can help you stay patient. The good news is that outside of peak times, many airports are processing passengers smoothly – but if you hit the peak, expect a wait.

The role of weather and cascading delays

Winter weather is a wildcard that can quickly turn a busy airport into a scene of widespread delays and crowding. Unlike a single thunderstorm in summer, winter storms often span large regions and last for days, affecting numerous airports at once. The impact on terminals is twofold: flight operations slow down, and passengers accumulate in the airport.

When snow, ice or fog strikes, airports may impose ground delays, lengthen the time between takeoffs, or require extensive de-icing of aircraft. For travelers, this can mean sitting on a plane at the gate longer, or waiting in the terminal as departure times slip. If one flight is delayed, the passengers for it remain in the gate area – and if that overlaps with passengers arriving early for the next flight, gate lounges get overcrowded.

Multiply by dozens of flights and soon the whole terminal feels jam-packed. Europe’s air traffic agency notes that winter conditions often force arrival flow restrictions (for example, slowing the rate of landings in low visibility), which leads to planes holding or being delayed on the ground. Those delayed inbound planes then cause later outbound flights to depart late, in a chain reaction.

A stark illustration came on a mid-November weekend in Germany: freezing fog in the morning combined with a shortfall of de-icing trucks led to 41 flight cancellations and 858 delays in a single day across the country’s major airports. Frankfurt and Munich were hardest hit, and the disruption rippled into the next day. Ground handling teams reported that illness had thinned their ranks, so there simply weren’t enough crews to de-ice scores of planes at once.

As a result, many flights missed their scheduled slots. Passengers in Munich found themselves waiting extra hours in terminals, with airlines scrambling to rebook connections and even putting some travelers on trains as alternatives. This episode shows how weather + a minor resource crunch (not enough staff or equipment) can snowball into significant delays. Unions in Germany cautioned that with such tight staffing, “any weather event can quickly snowball into system-wide chaos”.

In North America, winter storms have already disrupted travel post-Thanksgiving. On one busy Sunday, over 12,000 flights were delayed and 1,000 cancelled across the U.S. due to a mix of snow and severe weather. Chicago O’Hare – a major hub – was hit the hardest with cascading delays, and even airports not directly in the storm (like Atlanta) saw knock-on effects.

As a travel expert explained, “the aviation system is really interconnected, and it can have a domino effect – you can be impacted even without being in the area that’s seeing weather”. For instance, Atlanta had clear skies but still experienced slowdowns because many connecting flights nationwide were coming from snowy regions. When flights get cancelled, large numbers of stranded passengers may line up at service desks or camp out awaiting new flights, adding to terminal crowding.

Winter weather also affects airport infrastructure: snow piles need clearing, runways may close for plowing, and shuttle transportation might be delayed, all of which can keep travelers stuck in terminals longer. A closed runway means departing flights queue up (and passengers linger in gate areas), while arriving flights might divert or sit on taxiways.

If major highways or rail links to the airport are closed by storms, passengers might arrive late en masse once transport reopens. Airports do prepare for this – for example, Munich Airport boasts a large fleet of snowplows and tries to keep operations running even in heavy snow. But when nature hits hard, flight schedules unravel despite best efforts, and the people at the end of that chain reaction find themselves waiting in a very crowded airport.

The key advice is to anticipate weather-related disruptions as a possibility in winter. Monitor forecasts for your departure and destination cities. If a significant storm is forecast, airlines often issue waivers allowing free changes – taking an earlier flight or rerouting can save you from being stuck.

If you’re at the airport during delays, stay close to gate areas for announcements but also take advantage of airport amenities (grabbing a meal or finding a less crowded seating area) rather than standing shoulder-to-shoulder at the gate for hours.

Know that airports will be doing everything they can – including bringing in extra staff for de-icing, cots for stranded travelers, and constant updates via apps and screens – to manage the situation. Still, a winter storm is one factor no airport can fully control, so built-in patience and flexibility are your best tools.

When travelers should arrive for winter flights

One of the most common questions this season is: how early is early enough to get to the airport? With reports of long lines, many travelers are upping their usual buffer. The general rule of thumb still holds – about two hours before departure for domestic or short-haul international flights, and around three hours for long-haul flights.

Airports and airlines across the board echo this guidance. For example, the Port Authority of New York and New Jersey recently told holiday travelers to arrive at least 2 hours in advance for domestic flights and 3 hours for international flights at its major airports.

European hubs issue similar advice: travel management companies in Spain advised clients using Madrid to be at the airport a minimum of two hours before intra-Europe flights and three hours before intercontinental flights amid the December rush.

That said, you may wonder if those guidelines are sufficient given the current crowds. The answer depends on your specific airport and flight. At major hubs like Heathrow, Paris CDG or JFK, it’s wise to lean towards the upper end of the recommended time, especially if you’re flying at a peak period (early morning, or a weekend/holiday).

If your flight departs at 7:00 a.m., that might mean getting to the airport by 5:00 a.m., since pre-dawn hours can see large tour groups and business travelers all converging when security opens. Many seasoned travelers set even earlier targets in winter – e.g. arriving 3+ hours early for any international flight – not to stand in line the whole time, but to have a cushion if something unexpected occurs (a road delay en route, or a longer bag-drop line).

Airports have noted that too many extremely early arrivals can also cause crowding (people who show up 5-6 hours before departure might flood the check-in area before desks open). So there’s no need to overdo it. However, given the current climate, erring on the side of a bit more time is prudent.

Consider your personal situation: Do you have bags to check? Add extra time for that, since staffing shortages have led to some longer check-in and bag-drop queues on busy days. Are you traveling with young children, elderly relatives or someone with limited mobility? Build in more time so you’re not rushed – getting through security with a stroller or wheelchair can take longer.

If you’re flying domestically from a smaller airport that you know well, 90 minutes might still suffice, but only if you’re confident about crowds. For any big-city airport or international gateway, stick with two hours minimum, and more like three for global flights.

During peak holiday periods, even frequent flyers who normally breeze through with TSA PreCheck or priority status are budgeting extra time because the volume is unprecedented. Ultimately, it’s far better to have an extra 30 minutes on the airside to relax (or enjoy a coffee) than to be stuck in a security queue staring at your watch. This winter, give yourself the gift of time.

The Takeaway

Winter air travel in 2025 is busier and more unpredictable than in recent years, but it remains manageable with good preparation. High passenger demand, occasional weather disruptions and staffing pressures create fluctuations in airport performance, meaning some days run smoothly while others experience bottlenecks. Staying updated through official airport channels and planning for extra time can make the experience far less stressful.

A calm, proactive approach helps more than anything else. Arriving early, organizing your carry-on for security and remaining flexible if schedules shift will improve your chances of moving through crowds efficiently. Airport teams and airline staff are working under heavy demand, and patience from travelers can make challenging moments easier for everyone. Busy periods often come in waves, so even long lines tend to ease as traffic cycles through.

Although congestion may continue through the winter, many airports are expanding staffing, upgrading systems and refining communication with passengers. These improvements aim to reduce delays over time, but until they fully take hold, realistic expectations remain essential. With preparation, awareness and a steady mindset, you can navigate winter travel conditions confidently and reach your destination ready to enjoy the season.

FAQ

Q1. How early should I arrive at the airport for winter flights?
Plan for about two hours before domestic or short haul flights and around three hours before long haul flights. During winter 2025, crowds and weather can increase delays, so arriving a little earlier than usual is wise, especially at large hubs or on peak holiday travel days.

Q2. Are security wait times predictable or posted in advance?
Some airports post real time estimates on their websites or apps, and the TSA app provides crowd sourced waits for U.S. airports. These can help, but wait times change quickly. Early mornings and late afternoons are usually busiest. Always give yourself extra time in case lines build suddenly.

Q3. How does winter weather actually affect my flight?
Winter weather can cause de icing delays, longer spacing between aircraft, diversions, or preemptive cancellations if a major storm is forecast. Even if your departure airport is clear, delays can cascade throughout the network. Monitor your flight status closely and sign up for alerts.

Q4. How long of a layover do I need in winter to be safe?
Aim for at least one hour for domestic connections and two hours or more for international connections. Many experienced travelers choose three hours in winter to allow for de icing or minor delays. Short layovers increase the risk of misconnecting during winter operations.

Q5. Does fast track security or TSA PreCheck help during busy times?
Yes. Priority lanes are usually much faster than the standard queue and can save significant time. Still arrive early, since these programs do not bypass check in or border control and lines can still form.

Q6. How can I avoid missing my flight if the airport is very crowded?
Arrive early, check in online, travel with carry on luggage when possible, and listen for announcements. If your flight is close to departure while you are in security, notify staff. If you miss your flight, contact the airline promptly for rebooking.

Q7. Are delays more common in winter even on sunny days?
Yes. Cold temperatures require de icing, and congestion at busy airports can slow operations even without snow or storms. Delays in other cities can also affect your aircraft’s arrival.

Q8. Should I schedule morning or evening flights in winter?
Morning flights are generally more reliable because delays from earlier flights have not yet accumulated. Evening flights are more vulnerable to knock on disruptions from the full day’s schedule.

Q9. Does travel insurance help with winter disruptions?
Often yes. Many policies reimburse expenses for long delays, missed connections, or unexpected overnight stays due to weather. Check your policy for coverage limits and required documentation.

Q10. What is the best overall strategy for smooth winter air travel?
Arrive early, build in generous layovers, monitor flight status, consider priority security, travel with carry on luggage when possible, and stay flexible. These steps reduce stress and help you manage winter disruptions.

Research Notes

To understand how intense winter travel has become, I started with industry reporting from The Independent and International Airport Review, which both describe UK aviation heading into the busiest Christmas period on record, with passenger numbers surpassing pre-pandemic peaks. Heathrow’s own traffic update added concrete figures on record December volumes and confirmed that the airport now expects more than 84 million passengers over the full year, which helped anchor the broader trend in real numbers.

For the wider picture, I looked at Business Traveller’s analysis of global seat capacity for winter 2025, showing airlines flying fuller schedules than before the pandemic, and TSA and ABC coverage on U.S. holiday screening, where record crowds are passing through security in just a few peak weeks. To see how strain on the system plays out on the ground, I drew on VisaHQ’s reporting about weather-related delays and staff sickness at German airports, along with coverage of work-to-rule actions and strikes in Spain, which together illustrate how even small disruptions can ripple through an already packed winter schedule.